For almost 5,000 years, cannabis, commonly called marijuana/marihuana, has been known to have beneficial effects on a spectrum of physical disorders. The earliest records of its use are from China and India.

In the 5th century A.D., information about cannabis as a drug moved west along the trade routes to Persia and Arabia. First used as an analgesic and an antiseptic, other medicinal uses were developed as the herb spread throughout the Middle East, Africa, and Eastern Europe.

Perhaps the earliest known therapeutic use of cannabis was in the 28th century B.C. by the Chinese Emperor Shen-Nung, who prescribed the plant for beri-beri, constipation, "female weakness," gout, malaria, rheumatism, and absentmindedness. In the 20th century B.C. Egyptians used cannabis to treat sore eyes. Medicinal use of cannabis has a long history in India. Before the 10th century B.C. a cannabis preparation called bhang was used as an anesthetic and antiphlegmatic. By the second century A.D. it was also prescribed during surgical procedures as an analgesic.

Some medical practitioners in India today still prescribe cannabis to treat a wide variety of conditions. Cannabis also appeared in ancient Greece as a remedy for earache, edema, and inflammation; while Africans used it to restore appetite, to relieve hemorrhoids and as an antiseptic.

Initially Western medicine made limited use of cannabis for the treatment of burns. But after Napoleon’s forces proved the drug’s efficacy as a pain reliever and sedative, cannabis became widely accepted in France and the rest of Europe. After 1840 the work of physicians such as O’Shaughnessy, Aubert-Roche, and Moreau de Tours drew further attention to cannabis use.

Cannabis use quickly spread to the U.S. and in 1860 its therapeutic applications were reported by the Committee on Cannabis Indica of the Ohio State Medical Society. The report listed claims of cannabis being successfully used to treat neuralgic pain, dysmenorhea, uterine hemorrhage, hysteria, delirium tremens, mania, palsy, whooping cough, infantile convulsions, asthma, gonorrhea, nervous rheumatism, chronic bronchitis, muscular spasms, tetanus, epilepsy, and appetite stimulation. From 1840-1890 over 100 articles were published recommending it for various disorders.

Prompted by the increasing use of marijuana as an intoxicant, the India Hemp Commission was established in 1893 to examine the drug’s position in that country. In addition to treatments mentioned in the Ohio State report, the Commission found cannabis used as an energy restorer, a hemostat, an ecbolic, and an antidiaretic. Medical conditions treated by cannabis included hay fever, cholera, dysentery, diabetes, impotence, urinary incontinence, swelling of the testicles, and granulation of open sores.

At about the same time, however, other medications were being developed with a more consistent and dependable result per dose, which led to a decline in marijuana use and the loss of support from the medical profession. This trend continued until, between 1856-1937, cannabis came to be considered almost solely as an intoxicant. One notable exception was a 1937 statement by Dr. William C. Woodward, the Legislative Counsel to the AMA and an opponent of cannabis use, who stated before a Hearing on the Taxation of Marijuana in the House of Representatives that marijuana "has remarkable properties in revealing the subconscious; hence, it can be used for psychological, psychoanalytic and psychotherapeutic research."
Despite the near-disappearance of medicinal cannabis use in the West, it still figures prominently in the Ayruvedic, Unani, and Tibbi systems of medicine found on the Indian-Pakistani subcontinent. Both a liquid extract and a tincture of cannabis are mentioned in the 1954 and 1966 Pharmacopoeias of India. A 1962 Bulletin on Narcotics describes frequent use in India of cannabis "as a sedative, hypnotic, analgesic, anti-spasmodic, and anti-hemorrhoidal."

Some Canadian and American scientists and doctors seem to feel that marijuana’s medical usefulness has been ignored and the drug removed from further research due to cannabis’ "unsavory reputation" as much as any scientific evidence discounting its therapeutic effects. Not all authorities are willing to abandon cannabis in favor of more readily acceptable medications, however. In his 1968 The Marijuana Papers, David Solomon argues that:
Marijuana should be accorded the medical status it once had in this country as a legitimate prescription item. After 1937, with the passage of the Marijuana Tax Act and subsequent federal and state legislation, it became virtually impossible for physicians to obtain or prescribe marijuana preparations for their patients. Thus, the medical profession was denied access to a versatile pharmaceutical tool with a history of therapeutic utility going back thousands of years.

A 1970 article, "Pot Facing Stringent Scientific Examination," claims that chemical and animal experiments are still ongoing into the medicinal use of marijuana for analgesia-mood elevation, blood pressure reduction-hypertension, and psychotherapeutic uses such as antidepressants and antianxiety drugs.

Other proponents of marijuana studies have urged that research be conducted into a wide variety of possible medicinal characteristics of cannabis, including: anticonvulsant effects (treatment of tetanus, convulsions of rabies, epilepsy, and infant convulsions), psychotherapeutic actions (appetite stimulation, treatment of depression, anxiety reduction as a sedative and hypnotic, treatment of addiction), antibiotic properties, and pain-affecting power. Along with the above-mentioned, T.H. Mikuriya, in his 1968 paper "Marijuana in Medicine: Past, Present and Future," suggests these additional possible therapeutic uses of THC and similar products: "prophylactic and treatment of neuralgias, including migraine and tic douloureaux, tranquilizer, anti-asthmatic, oxytocic, anti-tussive, topical anesthetic, withdrawal agent for opiate and alcohol addiction, and childbirth analgesic."

Throughout the 20th century, even limited research into the medical uses of marijuana has yielded new and exciting results. A 1972 study by Frank into the use of cannabis to reduce interocular pressure found that as the dose of marijuana increased, the pressure within the eye decreased by up to 30% in persons with normal eyes as well as in those suffering from glaucoma.

Czechoslovakia seems to be one of the leading countries in medical marijuana testing. In 1952 research there found that both an alcohol extract of cannabis and an externally applied paste form were bacterially effective against many gram-positive and one gram-negative microorganisms. Dr. J. Kabelikovi reported that out of the 2,000 herbs in that study, cannabis indica had the most promise as an antibiotic.

Other countries pursuing cannabis research include Argentina, Rhodesia, England, United States, Basutoland, and Mexico. Cannabis appears in a variety of forms in these studies, including ground-up seeds, a poultice of fresh leaves, tobacco, a mouthwash, a beverage, dusting powder, ear drops, alcohol solutions with glycerine, and dentin powder, as well as in a synthetic cannabis-like drug (Pyrahexyl). Interestingly enough, many of the medical applications of cannabis now being tested are the same treatments for which cannabis has been successfully used as a folk remedy since ancient times.